


Pulse

by secretagentfan



Category: Fire Emblem: Fuukasetsugetsu | Fire Emblem: Three Houses
Genre: Divine Pulse (Fire Emblem), Getting Together, M/M, Time Loop, silver snow
Language: English
Status: Completed
Published: 2021-02-20
Updated: 2021-02-20
Packaged: 2021-03-16 14:35:26
Rating: Teen And Up Audiences
Warnings: Graphic Depictions Of Violence
Chapters: 1
Words: 2,456
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/29577594
Author URL: https://archiveofourown.org/users/secretagentfan/pseuds/secretagentfan
Summary: Does "getting together" count when it happens in the heat of battle and only Byleth can remember?Byleth and Seteth try to survive Ailell. The Divine Pulse helps. Sort of.Written for Courage My Love zine
Relationships: My Unit | Byleth/Seteth
Comments: 2
Kudos: 22
Collections: Courage My Love: A Setleth Zine





	Pulse

**Author's Note:**

> Almost forgot to post this one!!!!  
> I love Byleth and Seteth so much.

_1_

The heat is unbearable, exhausting, but they’re alive. Gwendal is dead, and they’re alive. Now it’s just a matter of helping Judith take out the rest of his troops and getting the hell out of this wretched valley. They’re almost done, and that fact alone fills the air with a giddy sort of tension. The promise of relief, not just eventually, but _soon_.

“Drink this,” Seteth says, and Byleth struggles to comply, because his vision is blurring at the edges, and there’s blood running down his leg from a stab wound somewhere on his abdomen.

“Focus,” Seteth’s voice is urgent. A calloused hand grips Byleth’s face and the elixir is fed into his mouth in a hurry. Somewhere behind them lava bubbles, sparks and pops.

The wound closes and heals. Byleth can stand on his own now, so he does, and Seteth sloppily reverses the strangely effortless embrace they had managed, leaning on Byleth in a rare moment of weakness. Soot is in his usually perfectly kempt hair, and he’s clearly favoring his left leg. His wyvern flies above them, gaze watchful and possessive, proving that even resting and injured, Seteth is prepared for something to go wrong.

Seteth drinks the other half of the elixir without hesitation, and it’s testament to how exhausted he is that he doesn’t wipe off the lip of the bottle like he usually does.

“Some trap,” Byleth says, finally, over the tiny crackle of heat in his stomach that has absolutely nothing to do with the lava. He’s grown used to that, fighting alongside this man. Seteth makes a derisive sound that somehow, sounds a bit like a laugh.

“Some trap,” he confirms. Their faces are close, and Seteth’s breath puffs against Byleth’s face when he talks. “If you ever have the intent of running headlong into such a trap again, take care to warn me first. That was incredibly dangerous.”

“I did fine,” Byleth says, and Seteth makes a face. It’s ridiculous – so steeped in pure, unbridled, Setethian disapproval that it makes something light bubble up in Byleth’s chest. He can practically picture Seteth snapping a quill in his hand.

He laughs. It isn’t unpleasant at all. Buoyant and free. _I’m alive,_ Byleth thinks, somehow, and that’s all he thinks, because Seteth is cupping his cheeks. “You’re impossible,” he grunts.

Byleth nods, brain made of cotton. His eyes linger on his older friend’s mouth—a terrible idea really. “You did fine too,” he clarifies.

Something flashes in Seteth’s eyes, something fond and exhausted. Byleth doesn’t have time to consider it, because rough lips are against his now, firm, indisputable.

Byleth is being kissed. Seteth is kissing him. These facts don’t entirely match up with any of the data Byleth has gathered from this trap-gone-wrong so far, but he doesn’t find it in him to care. Doesn’t find it in him to do anything but trust instincts he didn’t know he had, and pull the man back in by his sweaty hair when he breaks away.

He shuts his eyes too this time, and Seteth’s hands move from his cheeks to his hips as their kiss softens and melts into something sweet, lingering.

Seteth breaks away. His eyes still are shut as he knocks their foreheads together.

“You must _think_ , Byleth, before you act. That could have gone very differently. Gwendal is an exceptional leader, and his men are loyal. Attacking _him_ only angers _them_ which can lead to unpredictable, unacceptable losses for our army—”

Byleth blinks rapidly, the lecture startling him more than the kiss, but this is Seteth, after all, he’s not sure why it _should_ surprise him. He nods. Watches. The lecture tapers off, and realization slowly blooms on the wyvern lord’s red face.

“You kissed me,” Byleth provides.

“Yes,” Seteth confirms. Byleth’s pleased he received the statement as the question it was intended to be. “You returned the kiss.”

“Yes,” Byleth replies.

For a moment, they just stand there. Byleth vaguely recognizes he dropped the Sword of the Creator at some point in that, and hurries to pick it up. Seteth’s hand is still locked over his own mouth when Byleth manages to get the blade at his hip once more.

“Seteth?” Byleth asks, and Seteth seems to come back to reality. In the distance, they both recognize the sound of clashing metal.

“After this battle,” Seteth says, slowly, taking Byleth’s hand. “We must discuss this properly. There is still so much to do.”

“After the battle,” Byleth agrees, but his reply is drowned out by a high scream. Seteth’s eyes go wide, his whole body jerking away.

_“Flayn!?”_

Flayn’s pegasus is falling, plummeting toward a bubbling lava pool. Byleth can make out what looks to be a silver arrow in its wing. Seteth is mounting his wyvern, but Byleth knows he won’t make it in time.

He activates the divine pulse before he can hear him scream.

* * *

_Pulse 2_

Byleth’s second pulse is faster. He resets to the top of the battle – not wanting to get stuck in an unwinnable situation. It’s a habit that began after Jeralt’s death; Byleth tries not to think about it.

He uses new tactics. Allows this reality to branch in a totally different direction. Caspar and Petra go to handle the traps, while he guards Flayn with Seteth.

The sound of melting metal and two screams interrupt his planning. One scream stops abruptly. The other does not.

Byleth hadn’t thought about the mages. Caspar’s body is unrecognizable; Petra is inconsolable. It’s his fault.

He resets.

* * *

_Pulse 3_

Ashe dies this time, not Caspar, not Flayn. Ashe had fired the arrow that killed her two pulses ago, so a part of Byleth feels like it’s almost justice, in a way.

It just doesn’t _feel_ like justice.

It hurts, actually. It hurts a lot. Byleth’s sword moved faster than his mind had, lashing out in defense, and Ashe had fallen so swiftly, so easily, and hit the ground so _hard_ all Byleth could think of was the way he would hold his teacup in both hands and smile as he talked about his siblings. His siblings that wouldn’t see him again because Byleth killed him.

“It’s over.”

Seteth’s hand is on his shoulder. Byleth hardly feels it, staring at the corpse of his former student. His freckles had gotten darker. He was still so young. The battle had been won but…

“I think I could have talked to him,” Byleth says, voice growing in volume. “I think I could have convinced him to join us.”

Arms are around him, firm, warm, reassuring. Seteth.

“I’m sorry,” Seteth says. “This was a great loss.”

Seteth wouldn’t remember this pulse, just like he didn’t remember last pulse, or the pulse before that. Byleth leans into the embrace and shuts his eyes anyway. The sounds of the army cleaning up, collecting their dead, and looting usable weapons fades into a gentle muffled hum. In this moment, the world feels perfectly still. Perfectly right.

Byleth could stay here forever, but his student is still dead. He has to go.

“I’m sorry too,” he whispers back, holding Seteth’s hand in his own and squeezing it, just once. “See you soon.”

“What—"

Reset.

* * *

_Pulse 6_

Ashe is out cold, thanks to Caspar, when they finally make it to Gwendal. The old man is an army in his own right. Byleth’s out of breath, and it takes all the focus he has to keep his sword in his hand. Seteth’s in a similar shape, ever at his side. His eyes are focused, calm, in spite of the blood and sweat.

An eerie peace overtakes them both on the battlefield: Byleth, neutral-faced and reckless, the Ashen Demon that tears down its enemies with relentless, wild abandon; Seteth, calm, patient, and calculated – each swing of his lance designed to deal the maximum amount of damage. Natural opposites shouldn’t work this well together, but time had been a good teacher. Byleth likes to think the tea parties helped too.

The rubble under Byleth’s feet is loose, and he stumbles. A mistake. Gwendal’s axe finds a home in his neck. It’s gruesome and horrible – Byleth doesn’t reset fast enough to block the pain out completely.

Seteth’s cry rings in his ears.

* * *

_Pulse 7_

Judith. Mages. Honestly, Byleth had just forgotten about her. Shit.

Reset.

* * *

_Pulse 9_

Byleth’s head is killing him. He’s over-using the divine pulse and that makes him sloppy. The sword that only hit his abdomen in the first pulse strikes a little closer to center this time, and his legs turn to jelly when it’s removed. He sways on his feet, vision fogging, and hits the ground shoulder first.

A green blur obliterates the soldier in a hurricane of blood and guts. A lance-wielder gets the drop on him without Byleth to guard his back. The spear enters and exits his chest with numbing speed. Byleth wants to scream.

His eyes focus just enough to notice Seteth reaching for him, bleeding, bleeding—

He grits his teeth, pushes past the impulse to black out, and reaches for whatever bit of Sothis he still has left in him.

Not like this.

Reset.

* * *

_Pulse 10_

“You must listen to me. Stand down, you’re in no condition to—”

Byleth tunes the voice out. His chest is heaving. He feels ill. His vision is covered with little black dots, and the sounds of clashing weaponry echoes in his head as well as his ears. He can’t keep doing this. The image of Jeralt’s corpse flashes behind his eyes and he locks it away. Not now.

It’s time for a bold choice.

“ _Byleth!_ ”

He steals a wyvern from an enemy soldier for quicker access to the other side of the battlefield. It’s a flashy tactic and draws enemy fire immediately. With the distraction, Caspar and Petra take out the mages.

“Woo-hoo!” Caspar shouts. “Now to Judith!”

Byleth smiles. Trap: solved. Judith: safe.

Now for Ashe.

Or at least, it would be time for Ashe, but Byleth’s hands are clammy, loosening on the reigns. He can’t seem to get any control over this wounded wyvern. It bucks and screeches, shaking him like a ragdoll, and—

Byleth is flying through the air now, wyvern-less, but he can see Ashe as he’s falling out of the sky. He’s running toward him, not pointing his bow at Flayn – a refreshing development. Seteth is yelling, but it’s a different yell than the usual one that happens when someone dies, so Byleth figures it’s fine, probably.

He hits the ground hard and rolls six times.

“Professor!” Ashe cries, and Byleth empties his lungs in a bloody cough.

_Professor_. He _knew_ it. He looks at Ashe, and attempts to contort his face into something reassuring, but it comes out as more of a grimace. Broken ribs. Possibly spine.

“Fight—with—us,” Byleth manages, through his teeth. Ashe’s eyes go wide.

“ _Professor_! Just—just hold on! Hold on, please!”

Ashe: solved. Now Gwendal. Byleth’s ears are ringing. He can’t pass out yet. Gwendal. Everything tastes like smoke and blood. He’s blacking out. No. No. _No._

A wyvern is landing near them, kicking up dirt and soot. Byleth knows who it is. His heart leaps; he’s in love, or maybe just lightheaded.

“Seteth—” he manages to get out, “take Ashe and— Dorothea and—”

_“Enough!_ Linhardt, help me here! _”_

His head is roughly pulled onto Seteth’s lap as elixir is fed into his mouth. Ah, this is familiar. This happened before, a while ago. Byleth reaches up to touch Seteth’s face, because it’s so familiar, but a flash of white light shakes all thoughts from his head. He cries out as his spine mends and his ribs snap into place. It’s agonizing. Consciousness is pulled from him forcefully. A darkness spreads somewhere behind his eyes, cold, empty. He fights it. If he passes out he can’t stop—can’t—keep an eye on—

The last thing he registers is Seteth’s hand, closed tight around his own. Byleth’s face is pressed against his broad chest, his kind heart beating against his ear, hummingbird fast.

What a mysterious, beautiful thing: a beating heart.

_Please._ Byleth thinks, desperate, fading. _Let me get to talk to you after this._

* * *

_The Infirmary_

Everything hurts, but that means Byleth isn’t dead. That’s good, he thinks, and tries to open his eyes. Too heavy. It doesn’t work.

There’s a steady scratching sound. A quill on parchment. Someone is writing. About a hundred different war meetings flash behind Byleth’s eyelids. He knows this sound. There’s only one person that writes like that, and it’s Seteth. Judging by the rate of the scratching - it’s Seteth in a _bad mood._

Byleth grunts, the sound coming out higher than he expects, and the scratching stops. He grits his teeth, putting forth all the energy he can muster to get his eyes half-open. He finds his vision much richer in pissed wyvern lord.

“You’re awake,” Seteth observes. His hand is on Byleth’s cheek, but Byleth hardly feels it. A thick bandage seems to have been taped there— maybe he scratched his face when he fell?

“You lost a great deal of blood. How are you feeling?”

Byleth thinks about how fingers work, wiggles them to get some sensation back, before managing a pathetic thumbs up. Seteth exhales through his nose, but some of the tension leaves his face.

Byleth can’t relax yet. _Gwendal_ , he manages to mouth, because his voice is still taking its time returning. How annoying. Seteth understands, at least. He pinches the bridge of his nose.

“Of course. He’s dead. The battle was a success. Judith has followed through on offering her aid, and everyone else is alive. No casualties.”

Byleth tries to find the words to inquire further but Seteth continues. “The boy you spoke to on the battlefield - our former student, Ashe - he’s alive as well. I’ve granted him access to his old room for the time being, while he determines where his place is in this war.”

Not a prisoner. Perfect. Byleth could cry. It worked. Everything had worked. He shut his eyes, and Seteth’s hand brushes his cheek again.

“You’re impossible,” Seteth grunts in a voice all too familiar.

Blood rushes to Byleth’s head. Memories pool behind his eyes. A kiss. A hug. Bloody green hair and dead, empty eyes— reaching, reaching.

He stares at Seteth, brain made of cotton.

“You stole a wyvern, flew into an enemy trap—” he lectures, raising a finger. “You must _think_ , Byleth, before you act—what are you—mmph!”

Byleth grips the front of Seteth’s cloak, pulling him in, shutting his eyes and locking their lips together fiercely. A few seconds pass, before Seteth leans into him, kissing back, returning it in full: firm, indisputable.


End file.
